953fa9cc40c1831dc52547a9d30a369560b6a1d7
1#include "cache.h"
2#include "oidmap.h"
3#include "object-store.h"
4#include "replace-object.h"
5#include "refs.h"
6#include "repository.h"
7#include "commit.h"
8
9static int register_replace_ref(const char *refname,
10 const struct object_id *oid,
11 int flag, void *cb_data)
12{
13 /* Get sha1 from refname */
14 const char *slash = strrchr(refname, '/');
15 const char *hash = slash ? slash + 1 : refname;
16 struct replace_object *repl_obj = xmalloc(sizeof(*repl_obj));
17
18 if (get_oid_hex(hash, &repl_obj->original.oid)) {
19 free(repl_obj);
20 warning("bad replace ref name: %s", refname);
21 return 0;
22 }
23
24 /* Copy sha1 from the read ref */
25 oidcpy(&repl_obj->replacement, oid);
26
27 /* Register new object */
28 if (oidmap_put(the_repository->objects->replace_map, repl_obj))
29 die("duplicate replace ref: %s", refname);
30
31 return 0;
32}
33
34static void prepare_replace_object(void)
35{
36 if (the_repository->objects->replace_map)
37 return;
38
39 the_repository->objects->replace_map =
40 xmalloc(sizeof(*the_repository->objects->replace_map));
41 oidmap_init(the_repository->objects->replace_map, 0);
42
43 for_each_replace_ref(register_replace_ref, NULL);
44
45 if (!the_repository->objects->replace_map->map.tablesize)
46 check_replace_refs = 0;
47}
48
49/* We allow "recursive" replacement. Only within reason, though */
50#define MAXREPLACEDEPTH 5
51
52/*
53 * If a replacement for object oid has been set up, return the
54 * replacement object's name (replaced recursively, if necessary).
55 * The return value is either oid or a pointer to a
56 * permanently-allocated value. This function always respects replace
57 * references, regardless of the value of check_replace_refs.
58 */
59const struct object_id *do_lookup_replace_object(const struct object_id *oid)
60{
61 int depth = MAXREPLACEDEPTH;
62 const struct object_id *cur = oid;
63
64 prepare_replace_object();
65
66 /* Try to recursively replace the object */
67 while (depth-- > 0) {
68 struct replace_object *repl_obj =
69 oidmap_get(the_repository->objects->replace_map, cur);
70 if (!repl_obj)
71 return cur;
72 cur = &repl_obj->replacement;
73 }
74 die("replace depth too high for object %s", oid_to_hex(oid));
75}